Improve keepalive offload documentation and error handling
Bug: 123987401
Test: atest FrameworksNetTests
Change-Id: Id651cfb743f02b05ca3845af3c393eaf5762bb20
diff --git a/core/java/android/net/TcpSocketKeepalive.java b/core/java/android/net/TcpSocketKeepalive.java
index 8f6ee7b..f691a0d 100644
--- a/core/java/android/net/TcpSocketKeepalive.java
+++ b/core/java/android/net/TcpSocketKeepalive.java
@@ -45,13 +45,14 @@
* - The application must not write to or read from the socket after calling this method, until
* onDataReceived, onStopped, or onError are called. If it does, the keepalive will fail
* with {@link #ERROR_SOCKET_NOT_IDLE}, or {@code #ERROR_INVALID_SOCKET} if the socket
- * experienced an error (as in poll(2) returned POLLERR); if this happens, the data received
- * from the socket may be invalid, and the socket can't be recovered.
+ * experienced an error (as in poll(2) returned POLLERR or POLLHUP); if this happens, the data
+ * received from the socket may be invalid, and the socket can't be recovered.
* - If the socket has data in the send or receive buffer, then this call will fail with
* {@link #ERROR_SOCKET_NOT_IDLE} and can be retried after the data has been processed.
- * An app could ensure this by using an application-layer protocol where it can receive
- * acknowledgement that it will go into keepalive mode. It could then go into keepalive
- * mode after having read the acknowledgement, draining the socket.
+ * An app could ensure this by using an application-layer protocol to receive acknowledgement
+ * that indicates all data has been delivered to server, e.g. HTTP 200 OK.
+ * Then the app could go into keepalive mode after reading all remaining data within the
+ * acknowledgement.
*/
@Override
void startImpl(int intervalSec) {
diff --git a/services/core/java/com/android/server/connectivity/KeepaliveTracker.java b/services/core/java/com/android/server/connectivity/KeepaliveTracker.java
index 6cff57d..cc4c173 100644
--- a/services/core/java/com/android/server/connectivity/KeepaliveTracker.java
+++ b/services/core/java/com/android/server/connectivity/KeepaliveTracker.java
@@ -239,7 +239,12 @@
.sendMessage(CMD_START_SOCKET_KEEPALIVE, slot, mInterval, mPacket);
break;
case TYPE_TCP:
- mTcpController.startSocketMonitor(mFd, this, mSlot);
+ try {
+ mTcpController.startSocketMonitor(mFd, this, mSlot);
+ } catch (InvalidSocketException e) {
+ handleStopKeepalive(mNai, mSlot, ERROR_INVALID_SOCKET);
+ return;
+ }
mNai.asyncChannel
.sendMessage(CMD_ADD_KEEPALIVE_PACKET_FILTER, slot, 0 /* Unused */,
mPacket);
diff --git a/services/core/java/com/android/server/connectivity/TcpKeepaliveController.java b/services/core/java/com/android/server/connectivity/TcpKeepaliveController.java
index 65de83b..3e21b5b 100644
--- a/services/core/java/com/android/server/connectivity/TcpKeepaliveController.java
+++ b/services/core/java/com/android/server/connectivity/TcpKeepaliveController.java
@@ -215,18 +215,20 @@
* Start monitoring incoming packets.
*
* @param fd socket fd to monitor.
- * @param messenger a callback to notify socket status.
+ * @param ki a {@link KeepaliveInfo} that tracks information about a socket keepalive.
* @param slot keepalive slot.
*/
public void startSocketMonitor(@NonNull final FileDescriptor fd,
- @NonNull final KeepaliveInfo ki, final int slot) {
+ @NonNull final KeepaliveInfo ki, final int slot)
+ throws IllegalArgumentException, InvalidSocketException {
synchronized (mListeners) {
if (null != mListeners.get(slot)) {
throw new IllegalArgumentException("This slot is already taken");
}
for (int i = 0; i < mListeners.size(); ++i) {
if (fd.equals(mListeners.valueAt(i))) {
- throw new IllegalArgumentException("This fd is already registered");
+ Log.e(TAG, "This fd is already registered.");
+ throw new InvalidSocketException(ERROR_INVALID_SOCKET);
}
}
mFdHandlerQueue.addOnFileDescriptorEventListener(fd, FD_EVENTS, (readyFd, events) -> {